5-Slot Carrier
The 5-Slot Carrier supports up to 5 modules—one Control Unit and four additional modules (expansion modules or PARTNER Mail VS). NULL

308 Module (Control Unit)
The 308 Module is the control unit or processor for the system, with 3 jacks for Caller ID compatible lines and 8 extensions. NULL

400E Module
The 400E/400EC Modules provide ports for 4 additional lines and no extensions, and is used with the 308 Module. The 400 EC Module supports Caller ID. NULL

2-Slot Carrier
The 2-Slot Carrier supports 2 modules—one Control Unit and one additional expansion module or PARTNER Mail VS® module. NULL

200E Module
The 200E Module provides ports for 2 additional lines & no extensions, and is used with the 308 Module. NULL

206E Module
The 206E/206EC Modules provide ports for 2 lines and 6 extensions and are used with the 308 Module in a 2-slot or 5-slot carrier. The 206EC Module supports Caller ID. NULL